Misalignment sensor

Abstract

In a disclosed embodiment, a steering axle wheel assembly for a vehicle is provided with a system for actively sensing and alerting a vehicle user of wheel misalignment. The wheel assembly includes an elongated tie rod extending between two wheels and a rotatable knuckle system connecting each wheel to a respective end of the tie rod. A steer angle, that is, the angle of a wheel with respect to an axle, is monitored. When the steer angle is significant, result in a tensile or compressive force is provided on the tie rod. This force on the tie rod is small when the steer angle is small. The tie rod is provided with a system to measure the force. An alerting system is provided which alerts a vehicle user when significant tensile or compressive force on the tie rod is measured, and the steer angle is small. Thus, a vehicle user is actively alerted of wheel misalignment.

What is claimed is:  
     
       1. A steering axle wheel assembly for a vehicle comprising: 
       a connecting system for connecting two wheels;  
       said connecting system including an elongated tie rod extending between two wheels;  
       a rotatable knuckle system connecting each wheel to a respective end of said tie rod;  
       said rotatable knuckle system including a kingpin defining an axis, and a knuckle which may rotate about said axis; and  
       said connecting system being equipped with a system for sensing wheel misalignment including a sensing device in the rotatable knuckle system which reflects an angle of rotation of said knuckle about said kingpin axis.  
     
     
       2. An assembly for a vehicle as set forth in claim  1 , wherein said tie rod is equipped with a sensor to measure tensile or compressive force. 
     
     
       3. An assembly for a vehicle as set forth in claim  2 , wherein said tie rod sensor is only actuated when said sensing device in the rotatable knuckle system determines the magnitude of said angle of rotation is below a limit. 
     
     
       4. An assembly for a vehicle as set forth in claim  2 , wherein said sensor to measure tensile or compressive force is connected to an alerting system to alert a vehicle user of wheel misalignment. 
     
     
       5. A steering axle wheel assembly for a vehicle comprising: 
       a connecting system for connecting two wheels,  
       said connecting system including an elongated tie rod extending between two wheels;  
       a rotatable knuckle system connecting each wheel to a respective end of said tie rod;  
       said rotatable knuckle system including a kingpin defining an axis, and a knuckle which may rotate about said axis,  
       a system for sensing wheel misalignment including a sensing device in the rotatable knuckle system which measures an angle of rotation of said knuckle about said kingpin axis;  
       said tie rod being equipped with a system to measure tensile or compressive force in response to said sensing device in the rotatable knuckle system and a control for determining if the magnitude of said measured force exceeds a predetermined amount when the magnitude of said measured angle is below a limit, and then indicating wheel misalignment.  
     
     
       6. An assembly for a vehicle as recited in claim  5 , wherein said tie rod system is only actuated when said sensing device determines the magnitude of an angle of rotation is below a limit. 
     
     
       7. A method for actively sensing wheel misalignment of a vehicle comprising the steps: 
       sensing and measuring the magnitude of an angle of rotation of a rotatable knuckle system about a kingpin,  
       measuring a force on a tie rod and activating an alerting system which alerts a vehicle user of wheel misalignment if the magnitude of said force is above a limit when said magnitude of the measured angle of rotation is below a limit.